Talk:Direction cosine

Notation[edit]

I think $\alpha$ , $\beta$ and $\gamma$ should represent angles instead of their cosine values. If they represent angles, then $\alpha$ , $\beta$ and $\gamma$ will mean $\langle \mathbf {v} ,{\hat {x}}\rangle$ , $\langle \mathbf {v} ,{\hat {y}}\rangle$ and $\langle \mathbf {v} ,{\hat {z}}\rangle$ respectively. I suggest we write $a=\cos \alpha$ and etc. instead. FrenzY DT (talk) 12:36, 3 October 2012 (UTC)[reply]

This article needs an explaining picture. — Preceding unsigned comment added by 129.69.222.156 (talk) 13:12, 22 January 2013 (UTC)[reply]

I'll make one now. M∧Ŝc²ħε И_τlk 17:02, 15 June 2013 (UTC)[reply]

Done. Also fixed the silly usage of tensor index notation (v₁, v₂, v₃) and Cartesian labels (v_x, v_y, v_z) on the vector coordinates, as well as the basis notation "i, j, k" and "x, y, 'z" to "e_x, e_y, e_z". Either use one notation or the other throughout, and not a mixture. M∧Ŝc²ħε И_τlk 18:07, 15 June 2013 (UTC)[reply]

Direction cosine vs direction cosines[edit]

The title seems wrong - I suggest it should be "Direction Cosines." A "direction cosine" by itself has no meaning except in the context of the 3D case. Even in 2D there is no "direction cosine" as the angles would be complementary . — Preceding unsigned comment added by Bubsir (talk • contribs) 19:13, 23 November 2015 (UTC)[reply]